Maandelijks archief: januari 2018

Artists were the Delaware Water Gap’s most effective discoverers. Inadvertently, they publicized it. They almost literally put it on the map. Arrested by the symmetries of this geomorphological phenomenon, they sketched, painted, and engraved it. The earliest dated work is the Strickland Aquatint, i830, with a long and narrow flat-bottomed Durham boat in the foreground on the river, four crewmen standing at their oars, a steersman (also standing) in the stem, and in the background the wildwoods rising up the mountain with its deep, improbable incision. Cutting and filling, a stream would cross its own valley, gradationally leaving gravels under sands under silts under muds under fine grains that settled in overbank floods. With co-working space amsterdam nothing missing, the sequence was before us now, and was many times reiterated in the rock-a history of the migrations of the stream as it spread layer upon layer through its subsiding valley, 412, 411, 410 million years ago. In i832, Asher B. Durand came upon the scene. Durand was one of the founders of what in time would be labelled the Hudson River School. The term was a pejorative laid by a critic on painters who went outdoors to vent their romantic spirits. They went up the Hudson, they went up the Rockies, and they went into the Water Gap unafraid. Durand painted another Durham boat. His trees looked Japanese. The picture was published after Durand himself made a copper engraving. It contributed to the axiom that where an easel had stood a hotel would follow. Kittatinny House was established in i833, sleeping twenty-five. Anita chipped out a piece of Bloomsburg conglomerateevidence in itself that the stream which had made it was by no means spent. The rolling Silurian countryside must have been lovely-its river valleys velvet green. There were highland jaspers among the pebbles in the sand. The co-working space rotterdam early geologists began arriving in i836, led by Henry Darwin Rogers. They were conducting Pennsylvania’s first geological survey. In the deep marine Martinsburg slate and in the mountain strata that stood above it-in the “plication” and the “corrugation” of the sediments-Rogers saw “stupendous crust-movement and revolution,” the “most momentous” of ancient times, and reported to Harrisburg what would eventually become known as the Taconic and Alleghenian orogenies. He decided that something had wrenched the mountain in New Jersey several hundred feet out of line with its counterpart in Pennsylvania.

I said I had always assumed that the skyline was shaped by human considerations-commercial, historical, ethnic. Who could imagine a Little Italy in a skyscraper, a linoleum warehouse up in the clouds? The towers of midtown, as one might imagine, were emplaced in substantial rock, Anita said-rock that once had been heated near the point of melting, had recrystallized, had been heated again, had recrystallized, and, while not particularly competent, was more than adequate to hold up those buildings. Most important, it was right at the surface. You could see it, in all its micaceous glitter, shining like silver in the outcrops of flexplek huren schiphol Central Park. Four hundred and fifty million years in age, it was called Manhattan schist. All through midtown, it
Book 2: In Suspect Terrain was at or near the surface, but in the region south of Thirtieth Street it began to fall away, and at Washington Square it descended abruptly. The whole saddle between midtown and Wall Street would be undeiwater, were it not filled with many tens of fathoms of glacial till. So there sat Greenwich Village, SoHo, Chinatown, on material that could not hold up a great deal more than a golf tee-on the ground-up wreckage of the Ramapos, on crushed Catskill, on odd bits of Nyack and Tenafly. In the Wall Street area, the bedrock does not return to the surface, but it comes within forty feet and is accessible for the footings of the tallest things in town. New York grew high on the advantage of its hard rock, and, New York being what it is, cities all over the world have attempted to resemble it. The skyline of flexplek huren utrecht nuclear Houston, for example, is a simulacrum of Manhattan’s. Houston rests on twelve thousand feet of montmorillonitic clay, a substance that, when moist, turns into mobile jelly. After taking so much money out of the ground, the oil companies of Houston have put hundreds of millions back in. Houston is the world’s foremost city in fat basements. Its tall buildings are magnified duckpins, bobbing in their own mire.

The magnetism over the centers of the ridges themselves was uniformly strong. Moving away from the ridges, the strong and weak stripes varied in width from a few kilometres to as many as eighty. Vine and Matthews, chatting over tea in Cambridge, thought of using this data to connect Harry Hess’s spreading seafloor to the time scale of paleomagnetic reversals. The match would turn out to be exact. The weaker stripes matched times when the earth’s magnetic field had been reversed, and the strong ones matched times when the magnetic pole was in the north. Moreover, the two sets of stripes-calendars, in effect, moving away from the ridge-seemed to be symmetrical. The seafloor was not only spreading. It was documenting its age. L. W. Morley, a Canadian, independently had reached the same conclusions. Vine and flexplek huren amsterdam Matthews’ paper was published in Nature in September, i963, and became salient in the development of plate tectonics. In January of the same year, Morley had submitted almost identical ideas to the editors of Nature, but they were not yet prepared to accept them, so Morley then submitted the paper in tl1e United States to the Journal of Geophysical Research, which rejected it summarily. Morley’s paper came back with a note telling him that his ideas were suitable for a cocktail party but not for a serious publication. Data confirming the Vine-Matthews hypothesis began to accumulate, nowhere more emphatically than in a magnetic profile of the seafloor made by the National Science Foundation’s ship Eltanin crossing the East Pacific Rise. The Eltanin’s data showed that the seafloor became older and older with distance from the spreading center, and with perfect symmetry for two thousand kilometres on either side. All through the nineteen-sixties, ships continued to cruise the oceans dragging magnetometers behind, and eventually computers were programmed to correlate the benthic data flexplek huren rotterdam with the surface wanderings of the ships. Potassium-argon dating had timed the earth’s magnetic reversals to apparent perfection for the last three and a half million years. Geologists at Columbia calcul<1;ted the rate of seafloor spreading for those years and then assumed the rate to have been constant through earlier time.

An obvious application was to run cyanide through old tailings piles to see what others had missed, and a fair amount of such work was done, in particular during the Depression. There had been so many nineteenth-century mines in Nevada, however, that Deffeyes was sure that some had been ignored. He meant to look for them, and the first basin he prospected was the C Floor of Firestone Library, up the hill from his office in Princeton. There he ran through books and journals and began compiling a catalogue of mines and mills in the Basin and Range that had produced more than a certain number of dollars’ worth of silver between i86o and igoo. He prefers not to bandy the number. He found them in many places, from barrelcactus country near the Colorado River to ranges near the Oregon line, from the Oquirrh Mountains of Utah to the eastern rampart of the Sierra Nevada. In all, he listed zakelijke energie twenty-five. The larger ones, like the Comstock, had been worked and reworked and cyanided to death, and “tourists were all over them like ants.” A scavenger had best consider lesser mines, out-of-the-way mines-the quick-shot enrichments, the small-fissure lodes, where towns grew and died in six years. He figured that any mine worth, say, a million dollars a hundred years ago would still be worth a million dollars, because the old mills at best extracted ninety per cent of the silver in the ores, and the ten per cent remaining would be worth about what the ninety per cent had been worth then. Pulling more books and journals off the shelves, he sought to learn if and where attention had been paid to various old mines in the nineteen-thirties, and wherever he discovered activity at that time he crossed off those mines. His next move was to buy aerial photographs from the United States Geological Survey. The pictures were in overlapping pairs, and each pair covered sixteen square miles. “You look at them with stereo equipment and you are zakelijke energie vergelijken a giant with eyeballs a mile apart and forty thousand feet in the air. God, do you have stereovision! Things jump off the earth. You look for tailings. You look for dumps. You look for the faint scars of roads. The environmentalists are right. A scar in this climate will last. It takes a long time for the terrain to erase a road. You try to reason like a miner. If this was a mine, now where would I go for water? If this was a mill here, by this stream, then where is the mine?

Geology might be better served by a straightforward system of numbers. The reaction of geologists, by and large, has been to look upon this suggestion as if it had come over a bridge that exists between two cultures. A Continental geologist, in i822, named eighty million years for the white cliffs of Dover, for the downs of Kent and Sussex, for the chalky ground of Cognac and Champagne. Related strata were spread out through Holland, Sweden, Denmark, Germany, and Poland. He called it Le Terrain Cretace. If that name was apt, his own was irresistible. He was J. J. d’Omalius d’Halloy. Triassic, Jurassic, Cretaceous. When the Cretaceous ended, the big marine reptiles had disappeared, the flying reptiles, the dinosaurs, the rudistid clams, and many species of fish, not to mention the total elimination or severe reduction of countless smaller species from the sea. At the same point in geologic time, the flood zakelijke energie basalts now known as the Deccan Traps came out of the mantle and quickly covered at least a million square kilometres in India, effectively stopping the upwelling of the ocean. An ocean gone stagnant would kill phytoplankton, which prosper in the currents of mixed-up seas. Break the food chain and creatures die out above the break. Phytoplankton are the base of the food chain. The Arctic Ocean, surrounded by continents that had drifted together, might have become in the Cretaceous the greatest lake in all eternity, and when the North Atlantic opened up enough to let the water flood the southern seas the life in them would have suffered a cold osmotic shock. Drastic fluctuations of sea level-also related, perhaps, to the separation of continents-might have caused changes in air temperature and ocean circulation that were enough to sunder the food chain. At the end of i979, a small group at the Lawrence Radiation Laboratory, in Berkeley-among them the physicist Luis Alvarez, winner of a Nobel Prize, and his son Walter, who is zakelijke energie vergelijken a geologist-brought forth a piece of science in which they presented the catastrophe as the effect of an Apollo Object colliding with the earth. An Apollo Object is an “earth-orbit-crossing” asteroid th.1.t is at least a kilometre in diameter and is in the category of asteroids that have pockmarked the surface of Mercury, Mars, and the moon, and the surface of the earth as well, although most of the evidence has been obscured here by erosion. Like the general run of meteorites, an Apollo Object could be expected to contain a percentage of iridium and other platinum-like metals at least a thousand times greater than the concentration of the same metals in the crust of the earth. In widely separated parts of the world-Italy, Denmark, New Zealand-the Berkeley researchers found a thin depositional band, often just a centimetre thick, that contains unearthly concentrations of iridium. Below that sharp line are abundant Cretaceous fossils, and above it they are gone. It marks precisely the end of Cretaceous time.

When the ocean came back, came up again, it spread inland over the salt, which was not so much dissolved as buried, under layers of sediment washing in from the continent. With the weight of more and more sediment, the layers of salt went deep. Salt has a low specific gravity and is very plastic. Pile eight thousand feet of sediment on it and it starts to move. Slowly, blobularly, it collects itself and moves. It shoves apart layers of rock. It mounds upon itself, and, breaking its way upward, rises in mushroom shape-a salt dome. Still rising into more shales and sandstones, it bends them into graceful arches and then bursts through them like a bullet shooting upward through a splintering floor. A plastic body moving like this is known as a diapir. The shape becomes a reverse teardrop. Generally, after the breakthrough, there will be some big layers of sandstone leaning on the
salt dome like boards leaning up against a wall. The sandstone is permeable and probably has a layer of shale above it, which is not permeable. Any fluid in the sandstone will not only be trapped under the shale zakelijke energie but will also be trapped by the impermeable salt. Enter the’ strange companionship of oil and salt. Oil also moves after it forms. You never find it where God put it. It moves great distances through permeable rock. Unless something traps it, it will move on upward until it reaches daylight and turns into tar.I You don’t run a limousine on tar, let alone a military-industrial complex. If, however, the oil moves upward through inclined sandstone1 and then hits a wall of salt, it stops, and stays-trapped. Run a little drill down the side of a salt dome and when you hit “sand” it may be full of oil. In the Gulf of Mexico were many of the bays that dried up covered with salt. Where the domes are now, there are towers in the Gulf. A number of salt domes are embedded in the Missirsippi Delta, and have been mined. There are rooms inside them with ceilings a hundred feet zakelijke energie vergelijken high-room after room after room, like convention halls, with walls, floors, and ceilings of salt, above ninety-nine per centre. I Deffeyes was saying, “It’s likely that in under this salt flat are mountain structures just as complicated as any of the ranges. They’re just buried.”

When I asked Deffe yes what one might expect from a close inspection of roadcuts, he said they were windows into the world as it was in other times. We made plans to take samples of highway rock. I suggested going north up some new interstate to see what the blasting had disclosed. He said if you go north, in most places on this continent, the geology does not greatly vary. You should proceed in the direction of the continent itself. Go west. I had been thinking of a weekend trip to Whiteface Mountain, or something like it, but now, suddenly, a vaulting alternative came to mind. What about Interstate 80, I asked him. It goes the distance. How would it be? “Absorbing,” he said. And he mused aloud: After 80 crosses the Border Fault, it pussyfoots along on morainal till that levelled up the fingers of the foldbelt hills. It does a similar dance with glacial debris in parts of Pennsylvania. It needs no assistance on the craton. It climbs a ramp to the Rockies and a fault-block staircase up the front of the Sierra. It is geologically shrewd. It was the route of animal migrations, and of human history that followed. It avoids melodrama, avoids the Grand Canyons, the Jackson Holes, the geologic operas of the country, but it would surely be a sound experience of the big picture, of the history, the construction, the components of the continent. And in all likelihood it would display in its roadcuts rock from every epoch and era. In seasons that followed, I would go back and forth across the interstate like some sort of shuttle working out on a loom, accompanying geologists on purposes of their own or being accompanied by them zakelijke energie vergelijken from cut to cut and coast to coast. At any location on earth, as the rock record goes down into time and out into earlier geographies it touches upon tens of hundreds of stories, wherein the face of the earth often changed, changed utterly, and changed again, like the face of a crackling fire. The rock beside the road exposes one or two levels of the column of time and generally implies what went on immediately below and what occurred (or never occurred) above. To tell all the stories would be to tell pretty much the whole of geology in many volumes across a fifty-foot shelf, a task for which I am in every conceivable way unqualified. I am a layman who has travelled with a small core sampling of academic and government geologists ranging in experience from a student to an eminence grise. I wish to make no attempt to speak for all geology or to sweep zakelijke energie in every fact that came along. I want to choose some things that interested me and through them to suggest the general history of the continent by describing events and landscapes that geologists see written in rocks.

Basin and Range also includes the long set piece on time. The time scale we more or less take for granted did not exist in the early nineteenth century. In fifty years or so, it was gradually assembled by amateurs (often medical doctors) who pieced this to that, saw which came earlier, and gave names to distinctive zones of time. As you try to follow the changing face of the earth, the role of time is of course all-important, and time in its quantity is very hard to sense. Pages 69-gg. In college, I majored in English. In college and in high school, I took various introductory courses in physics, chemistry, biology, and geology, but only out of idle interest or to discharge distributional requirements. Like all writing, writing about geology is zakelijke energie masochistic, mind-fracturing self-enslaved labor-a description that intensifies when the medium is rock. What then could explain such behavior? Why would someone out of one culture try to make prose out of the other? Why would someone who majored in English choose to write about rocks? Why would a person who works for something called a Humanities Council and teaches a university course called Humanistic Studies 440 undertake to write about geology? I believe those questions are answered in one paragraph from Basin and Range. Pages 31-32. With brief exceptions, I have lived all my life in Princeton, New Jersey, where I was educated in the public schools and at the university. When I was seventeen, I went off to Deerfield Academy, in Massachusetts, where a geologist named Frank Conklin presented his subject in a first-rate full-year course. Even then, I was an English-major designate, but in the decades of writing that followed-highly varied non-fiction writing, often involving natural scenes-the geology lay there to be tapped. Sooner or later in many of my projects, geology would be touched upon in one way or another, and I would ask the geologists of the Princeton faculty to help me get it right. There were some geological passages in books like The Pine Barrens and Encounters with the Archdruid, for example, and there were more in Coming into the Country, arising from a question I had long meant to ask. Obviously, the placer gold in the drainages of the Yukon was there because weather had broken up mountains and bestrewn the gold in the gravels of streams. That I thought I understood. But I wondered what had put the gold in the mountains in the first place. I called the Geology Department and zakelijke energie vergelijken talked with a professor who said he could not begin to answer the question. He had a preoccupying interest in Jurassic leaves. “Call Ken Deffeyes,” he said. “Deffeyes knows, or thinks he knows.” For me, Deffeyes put the gold in the mountains.